Implements core logic for Pixel Canvas

ui/compositor/paint_recorder.cc

Index: ui/compositor/paint_recorder.cc
diff --git a/ui/compositor/paint_recorder.cc b/ui/compositor/paint_recorder.cc
index 8a8c4c28caf55c97e0c6cc0c0bc55e86f98430cc..5d7fcf949970c3a500e7d35270979c1d676b2c60 100644
--- a/ui/compositor/paint_recorder.cc
+++ b/ui/compositor/paint_recorder.cc
@@ -20,28 +20,37 @@ namespace ui {
 // directly, then appends that to the |context|. If not, then this records
 // to the |context|'s PaintOpBuffer.
 PaintRecorder::PaintRecorder(const PaintContext& context,
-                             const gfx::Size& recording_size,
+                             const gfx::Size& effective_recording_size,

[oshima, 2017/06/15 22:59:12]

do you need this change?

[malaykeshav, 2017/06/16 20:41:57]

Added it to differentiate if from the other constructor in which the recording
size is always in DIPs while in this constructor the recording size should be in
pixels if Pixel canvas is enabled.

                              PaintCache* cache)
     : context_(context),
       record_canvas_(cache ? cache->ResetCache() : context_.list_->StartPaint(),
-                     gfx::RectToSkRect(gfx::Rect(recording_size))),
+                     gfx::RectToSkRect(gfx::Rect(effective_recording_size))),
       canvas_(&record_canvas_, context.device_scale_factor_),
       cache_(cache),
-      recording_size_(recording_size) {
+      recording_size_(effective_recording_size) {
 #if DCHECK_IS_ON()
   DCHECK(!context.inside_paint_recorder_);
   context.inside_paint_recorder_ = true;
 #endif
+  if (context_.IsPixelCanvas()) {
+    canvas()->Save();
+    canvas()->Scale(context.effective_scale_factor_x(),
+                    context.effective_scale_factor_y());
+  }
 }
 
 PaintRecorder::PaintRecorder(const PaintContext& context,
                              const gfx::Size& recording_size)
-    : PaintRecorder(context, recording_size, nullptr) {}
+    : PaintRecorder(context,
+                    context.ScaleToEffectivePixelSize(recording_size),
+                    nullptr) {}
 
 PaintRecorder::~PaintRecorder() {
 #if DCHECK_IS_ON()
   context_.inside_paint_recorder_ = false;
 #endif
+  if (context_.IsPixelCanvas())
+    canvas()->Restore();
   // If using cache, append what we've saved there to the PaintContext.
   // Otherwise, the content is already stored in the PaintContext, and we can
   // just close it.